<!DOCTYPE html>
<html>
<head>
  <style>
    .video-container {
      position: relative;
      padding-bottom: 56.25%; /* 16:9 aspect ratio (9 / 16 = 0.5625) */
      height: 0;
      overflow: hidden;
    }

    .video-container video {
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
    }
  </style>
</head>
<body>

<div class="video-container">
  <video controls>
    <source src="../video/oauth2_demo1.mp4" type="video/mp4">
    Your browser does not support the video tag.
  </video>
</div>

</body>
</html>
